SQLite

  unsigned char const *zNew = sqlite3_value_text(argv[2]);

  unsigned const char *z;         /* Pointer to token */
  int n;                          /* Length of token z */
  int token;                      /* Type of token */

  UNUSED_PARAMETER(NotUsed);
  if( zInput==0 || zOld==0 ) return;
  for(z=zInput; *z; z=z+n){
    n = sqlite3GetToken(z, &token);
    if( token==TK_REFERENCES ){
      char *zParent;
      do {
        z += n;
        n = sqlite3GetToken(z, &token);

*/
#ifdef SQLITE_DEBUG
static int cursorHoldsMutex(BtCursor *p){
  return sqlite3_mutex_held(p->pBt->mutex);
}
#endif



/*
** Invalidate the overflow cache of the cursor passed as the first argument.
** on the shared btree structure pBt.
*/
#define invalidateOverflowCache(pCur) (pCur->curFlags &= ~BTCF_ValidOvfl)





/*
** Invalidate the overflow page-list cache for all cursors opened
** on the shared btree structure pBt.
*/
static void invalidateAllOverflowCache(BtShared *pBt){
  BtCursor *p;
  assert( sqlite3_mutex_held(pBt->mutex) );
  for(p=pBt->pCursor; p; p=p->pNext){
    invalidateOverflowCache(p);
  }
}

#ifndef SQLITE_OMIT_INCRBLOB
/*
** This function is called before modifying the contents of a table
** to invalidate any incrblob cursors that are open on the
** row or one of the rows being modified.
**
** If argument isClearTable is true, then the entire contents of the
** table is about to be deleted. In this case invalidate all incrblob

  i64 iRow,               /* The rowid that might be changing */
  int isClearTable        /* True if all rows are being deleted */
){
  BtCursor *p;
  BtShared *pBt = pBtree->pBt;
  assert( sqlite3BtreeHoldsMutex(pBtree) );
  for(p=pBt->pCursor; p; p=p->pNext){
    if( (p->curFlags & BTCF_Incrblob)!=0 && (isClearTable || p->info.nKey==iRow) ){
      p->eState = CURSOR_INVALID;
    }
  }
}

#else
  /* Stub function when INCRBLOB is omitted */


  #define invalidateIncrblobCursors(x,y,z)
#endif /* SQLITE_OMIT_INCRBLOB */

/*
** Set bit pgno of the BtShared.pHasContent bitvec. This is called 
** when a page that previously contained data becomes a free-list leaf 
** page.

** is capable of reading or writing to the databse.  Cursors that
** have been tripped into the CURSOR_FAULT state are not counted.
*/
static int countValidCursors(BtShared *pBt, int wrOnly){
  BtCursor *pCur;
  int r = 0;
  for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
    if( (wrOnly==0 || (pCur->curFlags & BTCF_WriteFlag)!=0)
     && pCur->eState!=CURSOR_FAULT ) r++; 
  }
  return r;
}
#endif

/*
** If there are no outstanding cursors and we are not in the middle

  /* Now that no other errors can occur, finish filling in the BtCursor
  ** variables and link the cursor into the BtShared list.  */
  pCur->pgnoRoot = (Pgno)iTable;
  pCur->iPage = -1;
  pCur->pKeyInfo = pKeyInfo;
  pCur->pBtree = p;
  pCur->pBt = pBt;
  assert( wrFlag==0 || wrFlag==BTCF_WriteFlag );
  pCur->curFlags = wrFlag;
  pCur->pNext = pBt->pCursor;
  if( pCur->pNext ){
    pCur->pNext->pPrev = pCur;
  }
  pBt->pCursor = pCur;
  pCur->eState = CURSOR_INVALID;
  return SQLITE_OK;

    if( pCur->pNext ){
      pCur->pNext->pPrev = pCur->pPrev;
    }
    for(i=0; i<=pCur->iPage; i++){
      releasePage(pCur->apPage[i]);
    }
    unlockBtreeIfUnused(pBt);
    sqlite3DbFree(pBtree->db, pCur->aOverflow);
    /* sqlite3_free(pCur); */
    sqlite3BtreeLeave(pBtree);
  }
  return SQLITE_OK;
}

/*

#endif
#ifdef _MSC_VER
  /* Use a real function in MSVC to work around bugs in that compiler. */
  static void getCellInfo(BtCursor *pCur){
    if( pCur->info.nSize==0 ){
      int iPage = pCur->iPage;
      btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info);
      pCur->curFlags |= BTCF_ValidNKey;
    }else{
      assertCellInfo(pCur);
    }
  }
#else /* if not _MSC_VER */
  /* Use a macro in all other compilers so that the function is inlined */
#define getCellInfo(pCur)                                                      \
  if( pCur->info.nSize==0 ){                                                   \
    int iPage = pCur->iPage;                                                   \
    btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info);        \
    pCur->curFlags |= BTCF_ValidNKey;                                          \
  }else{                                                                       \
    assertCellInfo(pCur);                                                      \
  }
#endif /* _MSC_VER */

#ifndef NDEBUG  /* The next routine used only within assert() statements */
/*

    memcpy(pBuf, pPayload, nByte);
  }
  return SQLITE_OK;
}

/*
** This function is used to read or overwrite payload information
** for the entry that the pCur cursor is pointing to. The eOp

** argument is interpreted as follows:
**
**   0: The operation is a read. Populate the overflow cache.
**   1: The operation is a write. Populate the overflow cache.
**   2: The operation is a read. Do not populate the overflow cache.
**
** A total of "amt" bytes are read or written beginning at "offset".
** Data is read to or from the buffer pBuf.
**
** The content being read or written might appear on the main page
** or be scattered out on multiple overflow pages.
**

** If the current cursor entry uses one or more overflow pages and the
** eOp argument is not 2, this function may allocate space for and lazily 
** popluates the overflow page-list cache array (BtCursor.aOverflow). 
** Subsequent calls use this cache to make seeking to the supplied offset 
** more efficient.
**
** Once an overflow page-list cache has been allocated, it may be
** invalidated if some other cursor writes to the same table, or if
** the cursor is moved to a different row. Additionally, in auto-vacuum
** mode, the following events may invalidate an overflow page-list cache.
**
**   * An incremental vacuum,

){
  unsigned char *aPayload;
  int rc = SQLITE_OK;
  u32 nKey;
  int iIdx = 0;
  MemPage *pPage = pCur->apPage[pCur->iPage]; /* Btree page of current entry */
  BtShared *pBt = pCur->pBt;                  /* Btree this cursor belongs to */
#ifdef SQLITE_DIRECT_OVERFLOW_READ
  int bEnd;                                   /* True if reading to end of data */
#endif

  assert( pPage );
  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
  assert( cursorHoldsMutex(pCur) );
  assert( eOp!=2 || offset==0 );      /* Always start from beginning for eOp==2 */

  getCellInfo(pCur);
  aPayload = pCur->info.pCell + pCur->info.nHeader;
  nKey = (pPage->intKey ? 0 : (int)pCur->info.nKey);
#ifdef SQLITE_DIRECT_OVERFLOW_READ
  bEnd = (offset+amt==nKey+pCur->info.nData);
#endif

  if( NEVER(offset+amt > nKey+pCur->info.nData) 
   || &aPayload[pCur->info.nLocal] > &pPage->aData[pBt->usableSize]
  ){
    /* Trying to read or write past the end of the data is an error */
    return SQLITE_CORRUPT_BKPT;
  }

  /* Check if data must be read/written to/from the btree page itself. */
  if( offset<pCur->info.nLocal ){
    int a = amt;
    if( a+offset>pCur->info.nLocal ){
      a = pCur->info.nLocal - offset;
    }
    rc = copyPayload(&aPayload[offset], pBuf, a, (eOp & 0x01), pPage->pDbPage);
    offset = 0;
    pBuf += a;
    amt -= a;
  }else{
    offset -= pCur->info.nLocal;
  }

  if( rc==SQLITE_OK && amt>0 ){
    const u32 ovflSize = pBt->usableSize - 4;  /* Bytes content per ovfl page */
    Pgno nextPage;

    nextPage = get4byte(&aPayload[pCur->info.nLocal]);



    /* If the BtCursor.aOverflow[] has not been allocated, allocate it now.
    ** Except, do not allocate aOverflow[] for eOp==2.
    **
    ** The aOverflow[] array is sized at one entry for each overflow page
    ** in the overflow chain. The page number of the first overflow page is
    ** stored in aOverflow[0], etc. A value of 0 in the aOverflow[] array
    ** means "not yet known" (the cache is lazily populated).
    */
    if( eOp!=2 && (pCur->curFlags & BTCF_ValidOvfl)==0 ){
      int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
      if( nOvfl>pCur->nOvflAlloc ){
        Pgno *aNew = (Pgno*)sqlite3DbRealloc(
            pCur->pBtree->db, pCur->aOverflow, nOvfl*2*sizeof(Pgno)

        );
        if( aNew==0 ){
          rc = SQLITE_NOMEM;
        }else{
          pCur->nOvflAlloc = nOvfl*2;
          pCur->aOverflow = aNew;
        }
      }
      if( rc==SQLITE_OK ){
        memset(pCur->aOverflow, 0, nOvfl*sizeof(Pgno));
        pCur->curFlags |= BTCF_ValidOvfl;
      }
    }

    /* If the overflow page-list cache has been allocated and the
    ** entry for the first required overflow page is valid, skip
    ** directly to it.
    */
    if( (pCur->curFlags & BTCF_ValidOvfl)!=0 && pCur->aOverflow[offset/ovflSize] ){
      iIdx = (offset/ovflSize);
      nextPage = pCur->aOverflow[iIdx];
      offset = (offset%ovflSize);
    }


    for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){


      /* If required, populate the overflow page-list cache. */
      if( (pCur->curFlags & BTCF_ValidOvfl)!=0 ){
        assert(!pCur->aOverflow[iIdx] || pCur->aOverflow[iIdx]==nextPage);
        pCur->aOverflow[iIdx] = nextPage;
      }


      if( offset>=ovflSize ){
        /* The only reason to read this page is to obtain the page
        ** number for the next page in the overflow chain. The page
        ** data is not required. So first try to lookup the overflow
        ** page-list cache, if any, then fall back to the getOverflowPage()
        ** function.
        **
        ** Note that the aOverflow[] array must be allocated because eOp!=2
        ** here.  If eOp==2, then offset==0 and this branch is never taken.
        */

        assert( eOp!=2 );
        assert( pCur->curFlags & BTCF_ValidOvfl );
        if( pCur->aOverflow[iIdx+1] ){
          nextPage = pCur->aOverflow[iIdx+1];
        }else{

          rc = getOverflowPage(pBt, nextPage, 0, &nextPage);
        }
        offset -= ovflSize;
      }else{
        /* Need to read this page properly. It contains some of the
        ** range of data that is being read (eOp==0) or written (eOp!=0).
        */
#ifdef SQLITE_DIRECT_OVERFLOW_READ
        sqlite3_file *fd;

        /* If all the following are true:
        **
        **   1) this is a read operation, and 
        **   2) data is required from the start of this overflow page, and
        **   3) the database is file-backed, and
        **   4) there is no open write-transaction, and
        **   5) the database is not a WAL database,
        **   6) all data from the page is being read.
        **
        ** then data can be read directly from the database file into the
        ** output buffer, bypassing the page-cache altogether. This speeds
        ** up loading large records that span many overflow pages.
        */
        if( (eOp&0x01)==0                                      /* (1) */
         && offset==0                                          /* (2) */
         && (bEnd || a==ovflSize)                              /* (6) */
         && pBt->inTransaction==TRANS_READ                     /* (4) */
         && (fd = sqlite3PagerFile(pBt->pPager))->pMethods     /* (3) */
         && pBt->pPage1->aData[19]==0x01                       /* (5) */
        ){
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];
          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, (i64)pBt->pageSize*(nextPage-1));
          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

        {
          DbPage *pDbPage;
          rc = sqlite3PagerAcquire(pBt->pPager, nextPage, &pDbPage,
              ((eOp&0x01)==0 ? PAGER_GET_READONLY : 0)
          );
          if( rc==SQLITE_OK ){
            aPayload = sqlite3PagerGetData(pDbPage);
            nextPage = get4byte(aPayload);
            rc = copyPayload(&aPayload[offset+4], pBuf, a, (eOp&0x01), pDbPage);
            sqlite3PagerUnref(pDbPage);
            offset = 0;
          }
        }
        amt -= a;
        pBuf += a;
      }

  assert( pCur->eState==CURSOR_VALID );
  assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
  assert( pCur->iPage>=0 );
  if( pCur->iPage>=(BTCURSOR_MAX_DEPTH-1) ){
    return SQLITE_CORRUPT_BKPT;
  }
  rc = getAndInitPage(pBt, newPgno, &pNewPage,
               (pCur->curFlags & BTCF_WriteFlag)==0 ? PAGER_GET_READONLY : 0);
  if( rc ) return rc;
  pCur->apPage[i+1] = pNewPage;
  pCur->aiIdx[i+1] = 0;
  pCur->iPage++;

  pCur->info.nSize = 0;
  pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
  if( pNewPage->nCell<1 || pNewPage->intKey!=pCur->apPage[i]->intKey ){
    return SQLITE_CORRUPT_BKPT;
  }
  return SQLITE_OK;
}

#if 0

  );
#endif
  testcase( pCur->aiIdx[pCur->iPage-1] > pCur->apPage[pCur->iPage-1]->nCell );

  releasePage(pCur->apPage[pCur->iPage]);
  pCur->iPage--;
  pCur->info.nSize = 0;
  pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
}

/*
** Move the cursor to point to the root page of its b-tree structure.
**
** If the table has a virtual root page, then the cursor is moved to point
** to the virtual root page instead of the actual root page. A table has a

  if( pCur->iPage>=0 ){
    while( pCur->iPage ) releasePage(pCur->apPage[pCur->iPage--]);
  }else if( pCur->pgnoRoot==0 ){
    pCur->eState = CURSOR_INVALID;
    return SQLITE_OK;
  }else{
    rc = getAndInitPage(pCur->pBtree->pBt, pCur->pgnoRoot, &pCur->apPage[0],
                 (pCur->curFlags & BTCF_WriteFlag)==0 ? PAGER_GET_READONLY : 0);
    if( rc!=SQLITE_OK ){
      pCur->eState = CURSOR_INVALID;
      return rc;
    }
    pCur->iPage = 0;
  }
  pRoot = pCur->apPage[0];

  assert( pRoot->intKey==1 || pRoot->intKey==0 );
  if( pRoot->isInit==0 || (pCur->pKeyInfo==0)!=pRoot->intKey ){
    return SQLITE_CORRUPT_BKPT;
  }

  pCur->aiIdx[0] = 0;
  pCur->info.nSize = 0;
  pCur->curFlags &= ~(BTCF_AtLast|BTCF_ValidNKey|BTCF_ValidOvfl);


  if( pRoot->nCell>0 ){
    pCur->eState = CURSOR_VALID;
  }else if( !pRoot->leaf ){
    Pgno subpage;
    if( pRoot->pgno!=1 ) return SQLITE_CORRUPT_BKPT;
    subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);

    pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
    pCur->aiIdx[pCur->iPage] = pPage->nCell;
    rc = moveToChild(pCur, pgno);
  }
  if( rc==SQLITE_OK ){
    pCur->aiIdx[pCur->iPage] = pPage->nCell-1;
    pCur->info.nSize = 0;
    pCur->curFlags &= ~BTCF_ValidNKey;
  }
  return rc;
}

/* Move the cursor to the first entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.

int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
  int rc;
 
  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );

  /* If the cursor already points to the last entry, this is a no-op. */
  if( CURSOR_VALID==pCur->eState && (pCur->curFlags & BTCF_AtLast)!=0 ){
#ifdef SQLITE_DEBUG
    /* This block serves to assert() that the cursor really does point 
    ** to the last entry in the b-tree. */
    int ii;
    for(ii=0; ii<pCur->iPage; ii++){
      assert( pCur->aiIdx[ii]==pCur->apPage[ii]->nCell );
    }

    if( CURSOR_INVALID==pCur->eState ){
      assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage]->nCell==0 );
      *pRes = 1;
    }else{
      assert( pCur->eState==CURSOR_VALID );
      *pRes = 0;
      rc = moveToRightmost(pCur);
      if( rc==SQLITE_OK ){
        pCur->curFlags |= BTCF_AtLast;
      }else{
        pCur->curFlags &= ~BTCF_AtLast;
      }
   
    }
  }
  return rc;
}

/* Move the cursor so that it points to an entry near the key 
** specified by pIdxKey or intKey.   Return a success code.

  assert( cursorHoldsMutex(pCur) );
  assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
  assert( pRes );
  assert( (pIdxKey==0)==(pCur->pKeyInfo==0) );

  /* If the cursor is already positioned at the point we are trying
  ** to move to, then just return without doing any work */
  if( pCur->eState==CURSOR_VALID && (pCur->curFlags & BTCF_ValidNKey)!=0
   && pCur->apPage[0]->intKey 
  ){
    if( pCur->info.nKey==intKey ){
      *pRes = 0;
      return SQLITE_OK;
    }
    if( (pCur->curFlags & BTCF_AtLast)!=0 && pCur->info.nKey<intKey ){
      *pRes = -1;
      return SQLITE_OK;
    }
  }

  if( pIdxKey ){
    xRecordCompare = sqlite3VdbeFindCompare(pIdxKey);

          lwr = idx+1;
          if( lwr>upr ){ c = -1; break; }
        }else if( nCellKey>intKey ){
          upr = idx-1;
          if( lwr>upr ){ c = +1; break; }
        }else{
          assert( nCellKey==intKey );
          pCur->curFlags |= BTCF_ValidNKey;
          pCur->info.nKey = nCellKey;
          pCur->aiIdx[pCur->iPage] = (u16)idx;
          if( !pPage->leaf ){
            lwr = idx;
            goto moveto_next_layer;
          }else{
            *pRes = 0;

          nCell = (int)pCur->info.nKey;
          pCellKey = sqlite3Malloc( nCell );
          if( pCellKey==0 ){
            rc = SQLITE_NOMEM;
            goto moveto_finish;
          }
          pCur->aiIdx[pCur->iPage] = (u16)idx;
          rc = accessPayload(pCur, 0, nCell, (unsigned char*)pCellKey, 2);
          if( rc ){
            sqlite3_free(pCellKey);
            goto moveto_finish;
          }
          c = xRecordCompare(nCell, pCellKey, pIdxKey, 0);
          sqlite3_free(pCellKey);
        }

    }
    pCur->aiIdx[pCur->iPage] = (u16)lwr;
    rc = moveToChild(pCur, chldPg);
    if( rc ) break;
  }
moveto_finish:
  pCur->info.nSize = 0;
  pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
  return rc;
}


/*
** Return TRUE if the cursor is not pointing at an entry of the table.
**

  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  if( pCur->eState!=CURSOR_VALID ){
    invalidateOverflowCache(pCur);
    rc = restoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      *pRes = 0;
      return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
      *pRes = 1;

  ** to be invalid here. This can only occur if a second cursor modifies
  ** the page while cursor pCur is holding a reference to it. Which can
  ** only happen if the database is corrupt in such a way as to link the
  ** page into more than one b-tree structure. */
  testcase( idx>pPage->nCell );

  pCur->info.nSize = 0;
  pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
  if( idx>=pPage->nCell ){
    if( !pPage->leaf ){
      rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
      if( rc ){
        *pRes = 0;
        return rc;
      }

  int rc;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( *pRes==0 || *pRes==1 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  pCur->curFlags &= ~(BTCF_AtLast|BTCF_ValidOvfl);
  if( pCur->eState!=CURSOR_VALID ){
    if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
      rc = btreeRestoreCursorPosition(pCur);
      if( rc!=SQLITE_OK ){
        *pRes = 0;
        return rc;
      }

        pCur->eState = CURSOR_INVALID;
        *pRes = 1;
        return SQLITE_OK;
      }
      moveToParent(pCur);
    }
    pCur->info.nSize = 0;
    pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);

    pCur->aiIdx[pCur->iPage]--;
    pPage = pCur->apPage[pCur->iPage];
    if( pPage->intKey && !pPage->leaf ){
      rc = sqlite3BtreePrevious(pCur, pRes);
    }else{
      rc = SQLITE_OK;

  if( pCur->eState==CURSOR_FAULT ){
    assert( pCur->skipNext!=SQLITE_OK );
    return pCur->skipNext;
  }

  assert( cursorHoldsMutex(pCur) );
  assert( (pCur->curFlags & BTCF_WriteFlag)!=0 && pBt->inTransaction==TRANS_WRITE
              && (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );

  /* Assert that the caller has been consistent. If this cursor was opened
  ** expecting an index b-tree, then the caller should be inserting blob
  ** keys with no associated data. If the cursor was opened expecting an
  ** intkey table, the caller should be inserting integer keys with a

    /* If this is an insert into a table b-tree, invalidate any incrblob 
    ** cursors open on the row being replaced */
    invalidateIncrblobCursors(p, nKey, 0);

    /* If the cursor is currently on the last row and we are appending a
    ** new row onto the end, set the "loc" to avoid an unnecessary btreeMoveto()
    ** call */
    if( (pCur->curFlags&BTCF_ValidNKey)!=0 && nKey>0 && pCur->info.nKey==nKey-1 ){
      loc = -1;
    }
  }

  if( !loc ){
    rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc);
    if( rc ) return rc;

    assert( pPage->leaf );
  }
  insertCell(pPage, idx, newCell, szNew, 0, 0, &rc);
  assert( rc!=SQLITE_OK || pPage->nCell>0 || pPage->nOverflow>0 );

  /* If no error has occurred and pPage has an overflow cell, call balance() 
  ** to redistribute the cells within the tree. Since balance() may move
  ** the cursor, zero the BtCursor.info.nSize and BTCF_ValidNKey
  ** variables.
  **
  ** Previous versions of SQLite called moveToRoot() to move the cursor
  ** back to the root page as balance() used to invalidate the contents
  ** of BtCursor.apPage[] and BtCursor.aiIdx[]. Instead of doing that,
  ** set the cursor state to "invalid". This makes common insert operations
  ** slightly faster.
  **
  ** There is a subtle but important optimization here too. When inserting
  ** multiple records into an intkey b-tree using a single cursor (as can
  ** happen while processing an "INSERT INTO ... SELECT" statement), it
  ** is advantageous to leave the cursor pointing to the last entry in
  ** the b-tree if possible. If the cursor is left pointing to the last
  ** entry in the table, and the next row inserted has an integer key
  ** larger than the largest existing key, it is possible to insert the
  ** row without seeking the cursor. This can be a big performance boost.
  */
  pCur->info.nSize = 0;
  if( rc==SQLITE_OK && pPage->nOverflow ){
    pCur->curFlags &= ~(BTCF_ValidNKey);
    rc = balance(pCur);

    /* Must make sure nOverflow is reset to zero even if the balance()
    ** fails. Internal data structure corruption will result otherwise. 
    ** Also, set the cursor state to invalid. This stops saveCursorPosition()
    ** from trying to save the current position of the cursor.  */
    pCur->apPage[pCur->iPage]->nOverflow = 0;

  unsigned char *pCell;                /* Pointer to cell to delete */
  int iCellIdx;                        /* Index of cell to delete */
  int iCellDepth;                      /* Depth of node containing pCell */ 

  assert( cursorHoldsMutex(pCur) );
  assert( pBt->inTransaction==TRANS_WRITE );
  assert( (pBt->btsFlags & BTS_READ_ONLY)==0 );
  assert( pCur->curFlags & BTCF_WriteFlag );
  assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
  assert( !hasReadConflicts(p, pCur->pgnoRoot) );

  if( NEVER(pCur->aiIdx[pCur->iPage]>=pCur->apPage[pCur->iPage]->nCell) 
   || NEVER(pCur->eState!=CURSOR_VALID)
  ){
    return SQLITE_ERROR;  /* Something has gone awry. */

** parameters that attempt to write past the end of the existing data,
** no modifications are made and SQLITE_CORRUPT is returned.
*/
int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
  int rc;
  assert( cursorHoldsMutex(pCsr) );
  assert( sqlite3_mutex_held(pCsr->pBtree->db->mutex) );
  assert( pCsr->curFlags & BTCF_Incrblob );

  rc = restoreCursorPosition(pCsr);
  if( rc!=SQLITE_OK ){
    return rc;
  }
  assert( pCsr->eState!=CURSOR_REQUIRESEEK );
  if( pCsr->eState!=CURSOR_VALID ){

  /* Check some assumptions: 
  **   (a) the cursor is open for writing,
  **   (b) there is a read/write transaction open,
  **   (c) the connection holds a write-lock on the table (if required),
  **   (d) there are no conflicting read-locks, and
  **   (e) the cursor points at a valid row of an intKey table.
  */
  if( (pCsr->curFlags & BTCF_WriteFlag)==0 ){
    return SQLITE_READONLY;
  }
  assert( (pCsr->pBt->btsFlags & BTS_READ_ONLY)==0
              && pCsr->pBt->inTransaction==TRANS_WRITE );
  assert( hasSharedCacheTableLock(pCsr->pBtree, pCsr->pgnoRoot, 0, 2) );
  assert( !hasReadConflicts(pCsr->pBtree, pCsr->pgnoRoot) );
  assert( pCsr->apPage[pCsr->iPage]->intKey );

  return accessPayload(pCsr, offset, amt, (unsigned char *)z, 1);
}

/* 


** Mark this cursor as an incremental blob cursor.





*/
void sqlite3BtreeIncrblobCursor(BtCursor *pCur){



  pCur->curFlags |= BTCF_Incrblob;
}
#endif

/*
** Set both the "read version" (single byte at byte offset 18) and 
** "write version" (single byte at byte offset 19) fields in the database
** header to iVersion.

int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);

char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
struct Pager *sqlite3BtreePager(Btree*);

int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
void sqlite3BtreeIncrblobCursor(BtCursor *);
void sqlite3BtreeClearCursor(BtCursor *);
int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
void sqlite3BtreeCursorHints(BtCursor *, unsigned int mask);

#ifndef NDEBUG
int sqlite3BtreeCursorIsValid(BtCursor*);
#endif

** found at self->pBt->mutex. 
*/
struct BtCursor {
  Btree *pBtree;            /* The Btree to which this cursor belongs */
  BtShared *pBt;            /* The BtShared this cursor points to */
  BtCursor *pNext, *pPrev;  /* Forms a linked list of all cursors */
  struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */

  Pgno *aOverflow;          /* Cache of overflow page locations */


  CellInfo info;            /* A parse of the cell we are pointing at */
  i64 nKey;                 /* Size of pKey, or last integer key */
  void *pKey;               /* Saved key that was cursor last known position */
  Pgno pgnoRoot;            /* The root page of this tree */
  int nOvflAlloc;           /* Allocated size of aOverflow[] array */
  int skipNext;    /* Prev() is noop if negative. Next() is noop if positive */
  u8 curFlags;              /* zero or more BTCF_* flags defined below */


  u8 eState;                /* One of the CURSOR_XXX constants (see below) */



  u8 hints;                             /* As configured by CursorSetHints() */
  i16 iPage;                            /* Index of current page in apPage */
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
};

/*
** Legal values for BtCursor.curFlags
*/
#define BTCF_WriteFlag    0x01   /* True if a write cursor */
#define BTCF_ValidNKey    0x02   /* True if info.nKey is valid */
#define BTCF_ValidOvfl    0x04   /* True if aOverflow is valid */
#define BTCF_AtLast       0x08   /* Cursor is pointing ot the last entry */
#define BTCF_Incrblob     0x10   /* True if an incremental I/O handle */

/*
** Potential values for BtCursor.eState.
**
** CURSOR_INVALID:
**   Cursor does not point to a valid entry. This can happen (for example) 
**   because the table is empty or because BtreeCursorFirst() has not been
**   called.

  ** records into the sorter. */
  sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
  addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0); VdbeCoverage(v);
  regRecord = sqlite3GetTempReg(pParse);

  sqlite3GenerateIndexKey(pParse,pIndex,iTab,regRecord,0,&iPartIdxLabel,0,0);
  sqlite3VdbeAddOp2(v, OP_SorterInsert, iSorter, regRecord);
  sqlite3ResolvePartIdxLabel(pParse, iPartIdxLabel);
  sqlite3VdbeAddOp2(v, OP_Next, iTab, addr1+1); VdbeCoverage(v);
  sqlite3VdbeJumpHere(v, addr1);
  if( memRootPage<0 ) sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
  sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
                    (char *)pKey, P4_KEYINFO);
  sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR|((memRootPage>=0)?OPFLAG_P2ISREG:0));

    if( aRegIdx!=0 && aRegIdx[i]==0 ) continue;
    if( pIdx==pPk ) continue;
    VdbeModuleComment((v, "GenRowIdxDel for %s", pIdx->zName));
    r1 = sqlite3GenerateIndexKey(pParse, pIdx, iDataCur, 0, 1,
                                 &iPartIdxLabel, pPrior, r1);
    sqlite3VdbeAddOp3(v, OP_IdxDelete, iIdxCur+i, r1,
                      pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn);
    sqlite3ResolvePartIdxLabel(pParse, iPartIdxLabel);
    pPrior = pIdx;
  }
}

/*
** Generate code that will assemble an index key and stores it in register
** regOut.  The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
** the entry that needs indexing.  If pTab is a WITHOUT ROWID table, then
** iCur must be the cursor of the PRIMARY KEY index.
**
** Return a register number which is the first in a block of
** registers that holds the elements of the index key.  The
** block of registers has already been deallocated by the time
** this routine returns.
**
** If *piPartIdxLabel is not NULL, fill it in with a label and jump
** to that label if pIdx is a partial index that should be skipped.
** The label should be resolved using sqlite3ResolvePartIdxLabel().
** A partial index should be skipped if its WHERE clause evaluates
** to false or null.  If pIdx is not a partial index, *piPartIdxLabel
** will be set to zero which is an empty label that is ignored by
** sqlite3ResolvePartIdxLabel().
**
** The pPrior and regPrior parameters are used to implement a cache to
** avoid unnecessary register loads.  If pPrior is not NULL, then it is
** a pointer to a different index for which an index key has just been
** computed into register regPrior.  If the current pIdx index is generating
** its key into the same sequence of registers and if pPrior and pIdx share
** a column in common, then the register corresponding to that column already

  int regBase;
  int nCol;

  if( piPartIdxLabel ){
    if( pIdx->pPartIdxWhere ){
      *piPartIdxLabel = sqlite3VdbeMakeLabel(v);
      pParse->iPartIdxTab = iDataCur;
      sqlite3ExprCachePush(pParse);
      sqlite3ExprIfFalse(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel, 
                         SQLITE_JUMPIFNULL);
    }else{
      *piPartIdxLabel = 0;
    }
  }
  nCol = (prefixOnly && pIdx->uniqNotNull) ? pIdx->nKeyCol : pIdx->nColumn;

  }
  if( regOut ){
    sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regOut);
  }
  sqlite3ReleaseTempRange(pParse, regBase, nCol);
  return regBase;
}

/*
** If a prior call to sqlite3GenerateIndexKey() generated a jump-over label
** because it was a partial index, then this routine should be called to
** resolve that label.
*/
void sqlite3ResolvePartIdxLabel(Parse *pParse, int iLabel){
  if( iLabel ){
    sqlite3VdbeResolveLabel(pParse->pVdbe, iLabel);
    sqlite3ExprCachePop(pParse);
  }
}

      break;
    }
  }

  if( testAddr>=0 ){
    sqlite3VdbeJumpHere(v, testAddr);
  }
  sqlite3ExprCachePop(pParse);

  return rReg;
}
#endif /* SQLITE_OMIT_SUBQUERY */

#ifndef SQLITE_OMIT_SUBQUERY
/*

      /* The OP_Found at the top of this branch jumps here when true, 
      ** causing the overall IN expression evaluation to fall through.
      */
      sqlite3VdbeJumpHere(v, j1);
    }
  }
  sqlite3ReleaseTempReg(pParse, r1);
  sqlite3ExprCachePop(pParse);
  VdbeComment((v, "end IN expr"));
}
#endif /* SQLITE_OMIT_SUBQUERY */

/*
** Duplicate an 8-byte value
*/

    printf("PUSH to %d\n", pParse->iCacheLevel);
  }
#endif
}

/*
** Remove from the column cache any entries that were added since the
** the previous sqlite3ExprCachePush operation.  In other words, restore
** the cache to the state it was in prior the most recent Push.
*/
void sqlite3ExprCachePop(Parse *pParse){
  int i;
  struct yColCache *p;

  assert( pParse->iCacheLevel>=1 );
  pParse->iCacheLevel--;
#ifdef SQLITE_DEBUG
  if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
    printf("POP  to %d\n", pParse->iCacheLevel);
  }
#endif
  for(i=0, p=pParse->aColCache; i<SQLITE_N_COLCACHE; i++, p++){
    if( p->iReg && p->iLevel>pParse->iCacheLevel ){

        sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target);
        for(i=1; i<nFarg; i++){
          sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce);
          VdbeCoverage(v);
          sqlite3ExprCacheRemove(pParse, target, 1);
          sqlite3ExprCachePush(pParse);
          sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target);
          sqlite3ExprCachePop(pParse);
        }
        sqlite3VdbeResolveLabel(v, endCoalesce);
        break;
      }

      /* The UNLIKELY() function is a no-op.  The result is the value
      ** of the first argument.

                  pDef->funcFlags & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG);
          }
        }

        sqlite3ExprCachePush(pParse);     /* Ticket 2ea2425d34be */
        sqlite3ExprCodeExprList(pParse, pFarg, r1,
                                SQLITE_ECEL_DUP|SQLITE_ECEL_FACTOR);
        sqlite3ExprCachePop(pParse);      /* Ticket 2ea2425d34be */
      }else{
        r1 = 0;
      }
#ifndef SQLITE_OMIT_VIRTUALTABLE
      /* Possibly overload the function if the first argument is
      ** a virtual table column.
      **

        }
        nextCase = sqlite3VdbeMakeLabel(v);
        testcase( pTest->op==TK_COLUMN );
        sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL);
        testcase( aListelem[i+1].pExpr->op==TK_COLUMN );
        sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target);
        sqlite3VdbeAddOp2(v, OP_Goto, 0, endLabel);
        sqlite3ExprCachePop(pParse);
        sqlite3VdbeResolveLabel(v, nextCase);
      }
      if( (nExpr&1)!=0 ){
        sqlite3ExprCachePush(pParse);
        sqlite3ExprCode(pParse, pEList->a[nExpr-1].pExpr, target);
        sqlite3ExprCachePop(pParse);
      }else{
        sqlite3VdbeAddOp2(v, OP_Null, 0, target);
      }
      assert( db->mallocFailed || pParse->nErr>0 
           || pParse->iCacheLevel==iCacheLevel );
      sqlite3VdbeResolveLabel(v, endLabel);
      break;

    case TK_AND: {
      int d2 = sqlite3VdbeMakeLabel(v);
      testcase( jumpIfNull==0 );
      sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2,jumpIfNull^SQLITE_JUMPIFNULL);
      sqlite3ExprCachePush(pParse);
      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
      sqlite3VdbeResolveLabel(v, d2);
      sqlite3ExprCachePop(pParse);
      break;
    }
    case TK_OR: {
      testcase( jumpIfNull==0 );
      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
      sqlite3ExprCachePush(pParse);
      sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull);
      sqlite3ExprCachePop(pParse);
      break;
    }
    case TK_NOT: {
      testcase( jumpIfNull==0 );
      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
      break;
    }

  switch( pExpr->op ){
    case TK_AND: {
      testcase( jumpIfNull==0 );
      sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull);
      sqlite3ExprCachePush(pParse);
      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
      sqlite3ExprCachePop(pParse);
      break;
    }
    case TK_OR: {
      int d2 = sqlite3VdbeMakeLabel(v);
      testcase( jumpIfNull==0 );
      sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, jumpIfNull^SQLITE_JUMPIFNULL);
      sqlite3ExprCachePush(pParse);
      sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull);
      sqlite3VdbeResolveLabel(v, d2);
      sqlite3ExprCachePop(pParse);
      break;
    }
    case TK_NOT: {
      testcase( jumpIfNull==0 );
      sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull);
      break;
    }

    **    }
    */
    case SQLITE_TESTCTRL_ALWAYS: {
      int x = va_arg(ap,int);
      rc = ALWAYS(x);
      break;
    }

    /*
    **   sqlite3_test_control(SQLITE_TESTCTRL_BYTEORDER);
    **
    ** The integer returned reveals the byte-order of the computer on which
    ** SQLite is running:
    **
    **       1     big-endian,    determined at run-time
    **      10     little-endian, determined at run-time
    **  432101     big-endian,    determined at compile-time
    **  123410     little-endian, determined at compile-time
    */ 
    case SQLITE_TESTCTRL_BYTEORDER: {
      rc = SQLITE_BYTEORDER*100 + SQLITE_LITTLEENDIAN*10 + SQLITE_BIGENDIAN;
      break;
    }

    /*   sqlite3_test_control(SQLITE_TESTCTRL_RESERVE, sqlite3 *db, int N)
    **
    ** Set the nReserve size to N for the main database on the database
    ** connection db.
    */
    case SQLITE_TESTCTRL_RESERVE: {

  /* Round nByte up to the next valid power of two */
  for(iFullSz=mem5.szAtom, iLogsize=0; iFullSz<nByte; iFullSz *= 2, iLogsize++){}

  /* Make sure mem5.aiFreelist[iLogsize] contains at least one free
  ** block.  If not, then split a block of the next larger power of
  ** two in order to create a new free block of size iLogsize.
  */
  for(iBin=iLogsize; iBin<=LOGMAX && mem5.aiFreelist[iBin]<0; iBin++){}
  if( iBin>LOGMAX ){
    testcase( sqlite3GlobalConfig.xLog!=0 );
    sqlite3_log(SQLITE_NOMEM, "failed to allocate %u bytes", nByte);
    return 0;
  }
  i = mem5.aiFreelist[iBin];
  memsys5Unlink(i, iBin);

  u32 cksum = 0;                   /* Checksum of string zMaster */

  assert( pPager->setMaster==0 );
  assert( !pagerUseWal(pPager) );

  if( !zMaster 
   || pPager->journalMode==PAGER_JOURNALMODE_MEMORY 
   || !isOpen(pPager->jfd)
  ){
    return SQLITE_OK;
  }
  pPager->setMaster = 1;

  assert( pPager->journalHdr <= pPager->journalOff );

  /* Calculate the length in bytes and the checksum of zMaster */
  for(nMaster=0; zMaster[nMaster]; nMaster++){
    cksum += zMaster[nMaster];
  }

          sqlite3VdbeAddOp4(v, OP_String8, 0, 4, 0, pIdx->zName, P4_TRANSIENT);
          sqlite3VdbeAddOp3(v, OP_Concat, 4, 3, 3);
          sqlite3VdbeAddOp2(v, OP_ResultRow, 3, 1);
          jmp4 = sqlite3VdbeAddOp1(v, OP_IfPos, 1); VdbeCoverage(v);
          sqlite3VdbeAddOp0(v, OP_Halt);
          sqlite3VdbeJumpHere(v, jmp4);
          sqlite3VdbeJumpHere(v, jmp2);
          sqlite3ResolvePartIdxLabel(pParse, jmp3);
        }
        sqlite3VdbeAddOp2(v, OP_Next, iDataCur, loopTop); VdbeCoverage(v);
        sqlite3VdbeJumpHere(v, loopTop-1);
#ifndef SQLITE_OMIT_BTREECOUNT
        sqlite3VdbeAddOp4(v, OP_String8, 0, 2, 0, 
                     "wrong # of entries in index ", P4_STATIC);
        for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){

  struct RowSetChunk *pChunk;    /* List of all chunk allocations */
  sqlite3 *db;                   /* The database connection */
  struct RowSetEntry *pEntry;    /* List of entries using pRight */
  struct RowSetEntry *pLast;     /* Last entry on the pEntry list */
  struct RowSetEntry *pFresh;    /* Source of new entry objects */
  struct RowSetEntry *pForest;   /* List of binary trees of entries */
  u16 nFresh;                    /* Number of objects on pFresh */
  u16 rsFlags;                   /* Various flags */
  int iBatch;                    /* Current insert batch */
};

/*
** Allowed values for RowSet.rsFlags
*/
#define ROWSET_SORTED  0x01   /* True if RowSet.pEntry is sorted */
#define ROWSET_NEXT    0x02   /* True if sqlite3RowSetNext() has been called */

** Check to see if element iRowid was inserted into the rowset as
** part of any insert batch prior to iBatch.  Return 1 or 0.
**
** If this is the first test of a new batch and if there exist entires
** on pRowSet->pEntry, then sort those entires into the forest at
** pRowSet->pForest so that they can be tested.
*/
int sqlite3RowSetTest(RowSet *pRowSet, int iBatch, sqlite3_int64 iRowid){
  struct RowSetEntry *p, *pTree;

  /* This routine is never called after sqlite3RowSetNext() */
  assert( pRowSet!=0 && (pRowSet->rsFlags & ROWSET_NEXT)==0 );

  /* Sort entries into the forest on the first test of a new batch 
  */

  if( p->pPrior ){
    rc = multiSelect(pParse, p, pDest);
    explainSetInteger(pParse->iSelectId, iRestoreSelectId);
    return rc;
  }
#endif













  /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and 
  ** if the select-list is the same as the ORDER BY list, then this query
  ** can be rewritten as a GROUP BY. In other words, this:
  **
  **     SELECT DISTINCT xyz FROM ... ORDER BY xyz
  **
  ** is transformed to:

                        ** one row of the input to the aggregator has been
                        ** processed */
    int iAbortFlag;     /* Mem address which causes query abort if positive */
    int groupBySort;    /* Rows come from source in GROUP BY order */
    int addrEnd;        /* End of processing for this SELECT */
    int sortPTab = 0;   /* Pseudotable used to decode sorting results */
    int sortOut = 0;    /* Output register from the sorter */
    int orderByGrp = 0; /* True if the GROUP BY and ORDER BY are the same */

    /* Remove any and all aliases between the result set and the
    ** GROUP BY clause.
    */
    if( pGroupBy ){
      int k;                        /* Loop counter */
      struct ExprList_item *pItem;  /* For looping over expression in a list */

      for(k=p->pEList->nExpr, pItem=p->pEList->a; k>0; k--, pItem++){
        pItem->u.x.iAlias = 0;
      }
      for(k=pGroupBy->nExpr, pItem=pGroupBy->a; k>0; k--, pItem++){
        pItem->u.x.iAlias = 0;
      }
      if( p->nSelectRow>100 ) p->nSelectRow = 100;
    }else{
      p->nSelectRow = 1;
    }


    /* If there is both a GROUP BY and an ORDER BY clause and they are
    ** identical, then it may be possible to disable the ORDER BY clause 
    ** on the grounds that the GROUP BY will cause elements to come out 
    ** in the correct order. It also may not - the GROUP BY may use a
    ** database index that causes rows to be grouped together as required
    ** but not actually sorted. Either way, record the fact that the
    ** ORDER BY and GROUP BY clauses are the same by setting the orderByGrp
    ** variable.  */
    if( sqlite3ExprListCompare(pGroupBy, sSort.pOrderBy, -1)==0 ){
      orderByGrp = 1;
    }
 
    /* Create a label to jump to when we want to abort the query */
    addrEnd = sqlite3VdbeMakeLabel(v);

    /* Convert TK_COLUMN nodes into TK_AGG_COLUMN and make entries in
    ** sAggInfo for all TK_AGG_FUNCTION nodes in expressions of the
    ** SELECT statement.

      /* Begin a loop that will extract all source rows in GROUP BY order.
      ** This might involve two separate loops with an OP_Sort in between, or
      ** it might be a single loop that uses an index to extract information
      ** in the right order to begin with.
      */
      sqlite3VdbeAddOp2(v, OP_Gosub, regReset, addrReset);
      pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pGroupBy, 0,
          WHERE_GROUPBY | (orderByGrp ? WHERE_SORTBYGROUP : 0), 0
      );
      if( pWInfo==0 ) goto select_end;
      if( sqlite3WhereIsOrdered(pWInfo)==pGroupBy->nExpr ){
        /* The optimizer is able to deliver rows in group by order so
        ** we do not have to sort.  The OP_OpenEphemeral table will be
        ** cancelled later because we still need to use the pKeyInfo
        */
        groupBySort = 0;

        sAggInfo.sortingIdxPTab = sortPTab = pParse->nTab++;
        sortOut = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp3(v, OP_OpenPseudo, sortPTab, sortOut, nCol);
        sqlite3VdbeAddOp2(v, OP_SorterSort, sAggInfo.sortingIdx, addrEnd);
        VdbeComment((v, "GROUP BY sort")); VdbeCoverage(v);
        sAggInfo.useSortingIdx = 1;
        sqlite3ExprCacheClear(pParse);

      }

      /* If the index or temporary table used by the GROUP BY sort
      ** will naturally deliver rows in the order required by the ORDER BY
      ** clause, cancel the ephemeral table open coded earlier.
      **
      ** This is an optimization - the correct answer should result regardless.
      ** Use the SQLITE_GroupByOrder flag with SQLITE_TESTCTRL_OPTIMIZER to 
      ** disable this optimization for testing purposes.  */
      if( orderByGrp && OptimizationEnabled(db, SQLITE_GroupByOrder) 
       && (groupBySort || sqlite3WhereIsSorted(pWInfo))
      ){
        sSort.pOrderBy = 0;
        sqlite3VdbeChangeToNoop(v, sSort.addrSortIndex);
      }

      /* Evaluate the current GROUP BY terms and store in b0, b1, b2...
      ** (b0 is memory location iBMem+0, b1 is iBMem+1, and so forth)
      ** Then compare the current GROUP BY terms against the GROUP BY terms
      ** from the previous row currently stored in a0, a1, a2...
      */

    return;
  }
  rc = sqlite3_open(zNewDb, &newDb);
  if( rc ){
    fprintf(stderr, "Cannot create output database: %s\n",
            sqlite3_errmsg(newDb));
  }else{
    sqlite3_exec(p->db, "PRAGMA writable_schema=ON;", 0, 0, 0);
    sqlite3_exec(newDb, "BEGIN EXCLUSIVE;", 0, 0, 0);
    tryToCloneSchema(p, newDb, "type='table'", tryToCloneData);
    tryToCloneSchema(p, newDb, "type!='table'", 0);
    sqlite3_exec(newDb, "COMMIT;", 0, 0, 0);
    sqlite3_exec(p->db, "PRAGMA writable_schema=OFF;", 0, 0, 0);
  }
  sqlite3_close(newDb);
}

/*
** If an input line begins with "." then invoke this routine to
** process that line.

      { "pending_byte",          SQLITE_TESTCTRL_PENDING_BYTE           },
      { "assert",                SQLITE_TESTCTRL_ASSERT                 },
      { "always",                SQLITE_TESTCTRL_ALWAYS                 },
      { "reserve",               SQLITE_TESTCTRL_RESERVE                },
      { "optimizations",         SQLITE_TESTCTRL_OPTIMIZATIONS          },
      { "iskeyword",             SQLITE_TESTCTRL_ISKEYWORD              },
      { "scratchmalloc",         SQLITE_TESTCTRL_SCRATCHMALLOC          },
      { "byteorder",             SQLITE_TESTCTRL_BYTEORDER              },
    };
    int testctrl = -1;
    int rc = 0;
    int i, n;
    open_db(p, 0);

    /* convert testctrl text option to value. allow any unique prefix

          } else {
            fprintf(stderr,"Error: testctrl %s takes a single int option\n",
                    azArg[1]);
          }
          break;

        /* sqlite3_test_control(int) */
        case SQLITE_TESTCTRL_PRNG_SAVE:
        case SQLITE_TESTCTRL_PRNG_RESTORE:
        case SQLITE_TESTCTRL_PRNG_RESET:
        case SQLITE_TESTCTRL_BYTEORDER:
          if( nArg==2 ){
            rc = sqlite3_test_control(testctrl);
            fprintf(p->out, "%d (0x%08x)\n", rc, rc);
          } else {
            fprintf(stderr,"Error: testctrl %s takes no options\n", azArg[1]);
          }
          break;

#define SQLITE_TESTCTRL_OPTIMIZATIONS           15
#define SQLITE_TESTCTRL_ISKEYWORD               16
#define SQLITE_TESTCTRL_SCRATCHMALLOC           17
#define SQLITE_TESTCTRL_LOCALTIME_FAULT         18
#define SQLITE_TESTCTRL_EXPLAIN_STMT            19
#define SQLITE_TESTCTRL_NEVER_CORRUPT           20
#define SQLITE_TESTCTRL_VDBE_COVERAGE           21
#define SQLITE_TESTCTRL_BYTEORDER               22
#define SQLITE_TESTCTRL_LAST                    22

/*
** CAPI3REF: SQLite Runtime Status
**
** ^This interface is used to retrieve runtime status information
** about the performance of SQLite, and optionally to reset various
** highwater marks.  ^The first argument is an integer code for

**
**    0.5 -> -10           0.1 -> -33        0.0625 -> -40
*/
typedef INT16_TYPE LogEst;

/*
** Macros to determine whether the machine is big or little endian,
** and whether or not that determination is run-time or compile-time.
**
** For best performance, an attempt is made to guess at the byte-order
** using C-preprocessor macros.  If that is unsuccessful, or if
** -DSQLITE_RUNTIME_BYTEORDER=1 is set, then byte-order is determined
** at run-time.
*/
#ifdef SQLITE_AMALGAMATION
const int sqlite3one = 1;
#else
extern const int sqlite3one;
#endif
#if (defined(i386)     || defined(__i386__)   || defined(_M_IX86) ||    \
     defined(__x86_64) || defined(__x86_64__) || defined(_M_X64)  ||    \
     defined(_M_AMD64) || defined(_M_ARM)     || defined(__x86)   ||    \
     defined(__arm__)) && !defined(SQLITE_RUNTIME_BYTEORDER)
# define SQLITE_BYTEORDER    1234
# define SQLITE_BIGENDIAN    0
# define SQLITE_LITTLEENDIAN 1
# define SQLITE_UTF16NATIVE  SQLITE_UTF16LE
#endif
#if (defined(sparc)    || defined(__ppc__))  \
    && !defined(SQLITE_RUNTIME_BYTEORDER)
# define SQLITE_BYTEORDER    4321
# define SQLITE_BIGENDIAN    1
# define SQLITE_LITTLEENDIAN 0
# define SQLITE_UTF16NATIVE  SQLITE_UTF16BE
#endif
#if !defined(SQLITE_BYTEORDER)
# define SQLITE_BYTEORDER    0     /* 0 means "unknown at compile-time" */
# define SQLITE_BIGENDIAN    (*(char *)(&sqlite3one)==0)
# define SQLITE_LITTLEENDIAN (*(char *)(&sqlite3one)==1)
# define SQLITE_UTF16NATIVE  (SQLITE_BIGENDIAN?SQLITE_UTF16BE:SQLITE_UTF16LE)
#endif

/*
** Constants for the largest and smallest possible 64-bit signed integers.
** These macros are designed to work correctly on both 32-bit and 64-bit
** compilers.
*/

#define WHERE_OMIT_OPEN_CLOSE  0x0010 /* Table cursors are already open */
#define WHERE_FORCE_TABLE      0x0020 /* Do not use an index-only search */
#define WHERE_ONETABLE_ONLY    0x0040 /* Only code the 1st table in pTabList */
#define WHERE_AND_ONLY         0x0080 /* Don't use indices for OR terms */
#define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
#define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
#define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
#define WHERE_SORTBYGROUP      0x0800 /* Support sqlite3WhereIsSorted() */

/* Allowed return values from sqlite3WhereIsDistinct()
*/
#define WHERE_DISTINCT_NOOP      0  /* DISTINCT keyword not used */
#define WHERE_DISTINCT_UNIQUE    1  /* No duplicates */
#define WHERE_DISTINCT_ORDERED   2  /* All duplicates are adjacent */
#define WHERE_DISTINCT_UNORDERED 3  /* Duplicates are scattered */

void sqlite3BitvecDestroy(Bitvec*);
u32 sqlite3BitvecSize(Bitvec*);
int sqlite3BitvecBuiltinTest(int,int*);

RowSet *sqlite3RowSetInit(sqlite3*, void*, unsigned int);
void sqlite3RowSetClear(RowSet*);
void sqlite3RowSetInsert(RowSet*, i64);
int sqlite3RowSetTest(RowSet*, int iBatch, i64);
int sqlite3RowSetNext(RowSet*, i64*);

void sqlite3CreateView(Parse*,Token*,Token*,Token*,Select*,int,int);

#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
  int sqlite3ViewGetColumnNames(Parse*,Table*);
#else

void sqlite3DeleteFrom(Parse*, SrcList*, Expr*);
void sqlite3Update(Parse*, SrcList*, ExprList*, Expr*, int);
WhereInfo *sqlite3WhereBegin(Parse*,SrcList*,Expr*,ExprList*,ExprList*,u16,int);
void sqlite3WhereEnd(WhereInfo*);
u64 sqlite3WhereOutputRowCount(WhereInfo*);
int sqlite3WhereIsDistinct(WhereInfo*);
int sqlite3WhereIsOrdered(WhereInfo*);
int sqlite3WhereIsSorted(WhereInfo*);
int sqlite3WhereContinueLabel(WhereInfo*);
int sqlite3WhereBreakLabel(WhereInfo*);
int sqlite3WhereOkOnePass(WhereInfo*, int*);
int sqlite3ExprCodeGetColumn(Parse*, Table*, int, int, int, u8);
void sqlite3ExprCodeGetColumnOfTable(Vdbe*, Table*, int, int, int);
void sqlite3ExprCodeMove(Parse*, int, int, int);
void sqlite3ExprCacheStore(Parse*, int, int, int);
void sqlite3ExprCachePush(Parse*);
void sqlite3ExprCachePop(Parse*);
void sqlite3ExprCacheRemove(Parse*, int, int);
void sqlite3ExprCacheClear(Parse*);
void sqlite3ExprCacheAffinityChange(Parse*, int, int);
void sqlite3ExprCode(Parse*, Expr*, int);
void sqlite3ExprCodeFactorable(Parse*, Expr*, int);
void sqlite3ExprCodeAtInit(Parse*, Expr*, int, u8);
int sqlite3ExprCodeTemp(Parse*, Expr*, int*);

int sqlite3ExprIsInteger(Expr*, int*);
int sqlite3ExprCanBeNull(const Expr*);
int sqlite3ExprNeedsNoAffinityChange(const Expr*, char);
int sqlite3IsRowid(const char*);
void sqlite3GenerateRowDelete(Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8);
void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*);
int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
void sqlite3ResolvePartIdxLabel(Parse*,int);
void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
                                     u8,u8,int,int*);
void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
int sqlite3OpenTableAndIndices(Parse*, Table*, int, int, u8*, int*, int*);
void sqlite3BeginWriteOperation(Parse*, int, int);
void sqlite3MultiWrite(Parse*);
void sqlite3MayAbort(Parse*);

*/
void sqlite3BtreeCursorList(Btree *p){
#ifdef SQLITE_DEBUG
  BtCursor *pCur;
  BtShared *pBt = p->pBt;
  for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
    MemPage *pPage = pCur->apPage[pCur->iPage];
    char *zMode = (pCur->curFlags & BTCF_WriteFlag) ? "rw" : "ro";
    sqlite3DebugPrintf("CURSOR %p rooted at %4d(%s) currently at %d.%d%s\n",
       pCur, pCur->pgnoRoot, zMode,
       pPage ? pPage->pgno : 0, pCur->aiIdx[pCur->iPage],
       (pCur->eState==CURSOR_VALID) ? "" : " eof"
    );
  }
#endif

    sqlite3VdbeMemSetRowSet(pIn1);
    if( (pIn1->flags & MEM_RowSet)==0 ) goto no_mem;
  }

  assert( pOp->p4type==P4_INT32 );
  assert( iSet==-1 || iSet>=0 );
  if( iSet ){
    exists = sqlite3RowSetTest(pIn1->u.pRowSet, iSet, pIn3->u.i);


    VdbeBranchTaken(exists!=0,2);
    if( exists ){
      pc = pOp->p2 - 1;
      break;
    }
  }
  if( iSet>=0 ){

  }
  break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */

#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VFilter P1 P2 P3 P4 *
** Synopsis: iplan=r[P3] zplan='P4'
**
** P1 is a cursor opened using VOpen.  P2 is an address to jump to if
** the filtered result set is empty.
**
** P4 is either NULL or a string that was generated by the xBestIndex
** method of the module.  The interpretation of the P4 string is left
** to the module implementation.

** a prior call to sqlite3VdbeMakeLabel().
*/
void sqlite3VdbeResolveLabel(Vdbe *v, int x){
  Parse *p = v->pParse;
  int j = -1-x;
  assert( v->magic==VDBE_MAGIC_INIT );
  assert( j<p->nLabel );
  if( ALWAYS(j>=0) && p->aLabel ){
    p->aLabel[j] = v->nOp;
  }
  p->iFixedOp = v->nOp - 1;
}

/*
** Mark the VDBE as one that can only be run one time.

      rc = SQLITE_ERROR;
      sqlite3_finalize(p->pStmt);
      p->pStmt = 0;
    }else{
      p->iOffset = pC->aType[p->iCol + pC->nField];
      p->nByte = sqlite3VdbeSerialTypeLen(type);
      p->pCsr =  pC->pCursor;
      sqlite3BtreeIncrblobCursor(p->pCsr);


    }
  }

  if( rc==SQLITE_ROW ){
    rc = SQLITE_OK;
  }else if( p->pStmt ){
    rc = sqlite3_finalize(p->pStmt);

        disableTerm(pLevel, pLoop->aLTerm[j]);
      }
    }
    pLevel->op = OP_VNext;
    pLevel->p1 = iCur;
    pLevel->p2 = sqlite3VdbeCurrentAddr(v);
    sqlite3ReleaseTempRange(pParse, iReg, nConstraint+2);
    sqlite3ExprCachePop(pParse);
  }else
#endif /* SQLITE_OMIT_VIRTUALTABLE */

  if( (pLoop->wsFlags & WHERE_IPK)!=0
   && (pLoop->wsFlags & (WHERE_COLUMN_IN|WHERE_COLUMN_EQ))!=0
  ){
    /* Case 2:  We can directly reference a single row using an

      WhereLoop *p = pWInfo->pLoops;
      pWInfo->pLoops = p->pNextLoop;
      whereLoopDelete(db, p);
    }
    sqlite3DbFree(db, pWInfo);
  }
}

/*
** Return TRUE if both of the following are true:
**
**   (1)  X has the same or lower cost that Y
**   (2)  X is a proper subset of Y
**
** By "proper subset" we mean that X uses fewer WHERE clause terms
** than Y and that every WHERE clause term used by X is also used
** by Y.
**
** If X is a proper subset of Y then Y is a better choice and ought
** to have a lower cost.  This routine returns TRUE when that cost 
** relationship is inverted and needs to be adjusted.
*/
static int whereLoopCheaperProperSubset(
  const WhereLoop *pX,       /* First WhereLoop to compare */
  const WhereLoop *pY        /* Compare against this WhereLoop */
){
  int i, j;
  if( pX->nLTerm >= pY->nLTerm ) return 0; /* X is not a subset of Y */
  if( pX->rRun >= pY->rRun ){
    if( pX->rRun > pY->rRun ) return 0;    /* X costs more than Y */
    if( pX->nOut > pY->nOut ) return 0;    /* X costs more than Y */
  }
  for(j=0, i=pX->nLTerm-1; i>=0; i--){
    for(j=pY->nLTerm-1; j>=0; j--){
      if( pY->aLTerm[j]==pX->aLTerm[i] ) break;
    }
    if( j<0 ) return 0;  /* X not a subset of Y since term X[i] not used by Y */
  }
  return 1;  /* All conditions meet */
}

/*
** Try to adjust the cost of WhereLoop pTemplate upwards or downwards so
** that:
**
**   (1) pTemplate costs less than any other WhereLoops that are a proper
**       subset of pTemplate
**
**   (2) pTemplate costs more than any other WhereLoops for which pTemplate
**       is a proper subset.
**
** To say "WhereLoop X is a proper subset of Y" means that X uses fewer
** WHERE clause terms than Y and that every WHERE clause term used by X is
** also used by Y.
*/
static void whereLoopAdjustCost(const WhereLoop *p, WhereLoop *pTemplate){
  if( (pTemplate->wsFlags & WHERE_INDEXED)==0 ) return;
  for(; p; p=p->pNextLoop){
    if( p->iTab!=pTemplate->iTab ) continue;
    if( (p->wsFlags & WHERE_INDEXED)==0 ) continue;
    if( whereLoopCheaperProperSubset(p, pTemplate) ){
      /* Adjust pTemplate cost downward so that it is cheaper than its 
      ** subset p */
      pTemplate->rRun = p->rRun;
      pTemplate->nOut = p->nOut - 1;
    }else if( whereLoopCheaperProperSubset(pTemplate, p) ){
      /* Adjust pTemplate cost upward so that it is costlier than p since
      ** pTemplate is a proper subset of p */
      pTemplate->rRun = p->rRun;
      pTemplate->nOut = p->nOut + 1;
    }
  }
}

/*
** Search the list of WhereLoops in *ppPrev looking for one that can be
** supplanted by pTemplate.
**
** Return NULL if the WhereLoop list contains an entry that can supplant
** pTemplate, in other words if pTemplate does not belong on the list.
**
** If pX is a WhereLoop that pTemplate can supplant, then return the
** link that points to pX.
**
** If pTemplate cannot supplant any existing element of the list but needs
** to be added to the list, then return a pointer to the tail of the list.
*/
static WhereLoop **whereLoopFindLesser(
  WhereLoop **ppPrev,
  const WhereLoop *pTemplate
){
  WhereLoop *p;
  for(p=(*ppPrev); p; ppPrev=&p->pNextLoop, p=*ppPrev){
    if( p->iTab!=pTemplate->iTab || p->iSortIdx!=pTemplate->iSortIdx ){
      /* If either the iTab or iSortIdx values for two WhereLoop are different
      ** then those WhereLoops need to be considered separately.  Neither is
      ** a candidate to replace the other. */
      continue;
    }
    /* In the current implementation, the rSetup value is either zero
    ** or the cost of building an automatic index (NlogN) and the NlogN
    ** is the same for compatible WhereLoops. */
    assert( p->rSetup==0 || pTemplate->rSetup==0 
                 || p->rSetup==pTemplate->rSetup );

    /* whereLoopAddBtree() always generates and inserts the automatic index
    ** case first.  Hence compatible candidate WhereLoops never have a larger
    ** rSetup. Call this SETUP-INVARIANT */
    assert( p->rSetup>=pTemplate->rSetup );

    /* If existing WhereLoop p is better than pTemplate, pTemplate can be
    ** discarded.  WhereLoop p is better if:
    **   (1)  p has no more dependencies than pTemplate, and
    **   (2)  p has an equal or lower cost than pTemplate
    */
    if( (p->prereq & pTemplate->prereq)==p->prereq    /* (1)  */
     && p->rSetup<=pTemplate->rSetup                  /* (2a) */
     && p->rRun<=pTemplate->rRun                      /* (2b) */
     && p->nOut<=pTemplate->nOut                      /* (2c) */
    ){
      return 0;  /* Discard pTemplate */
    }

    /* If pTemplate is always better than p, then cause p to be overwritten
    ** with pTemplate.  pTemplate is better than p if:
    **   (1)  pTemplate has no more dependences than p, and
    **   (2)  pTemplate has an equal or lower cost than p.
    */
    if( (p->prereq & pTemplate->prereq)==pTemplate->prereq   /* (1)  */
     && p->rRun>=pTemplate->rRun                             /* (2a) */
     && p->nOut>=pTemplate->nOut                             /* (2b) */
    ){
      assert( p->rSetup>=pTemplate->rSetup ); /* SETUP-INVARIANT above */
      break;   /* Cause p to be overwritten by pTemplate */
    }
  }
  return ppPrev;
}

/*
** Insert or replace a WhereLoop entry using the template supplied.
**
** An existing WhereLoop entry might be overwritten if the new template
** is better and has fewer dependencies.  Or the template will be ignored
** and no insert will occur if an existing WhereLoop is faster and has
** fewer dependencies than the template.  Otherwise a new WhereLoop is
** added based on the template.
**
** If pBuilder->pOrSet is not NULL then we care about only the
** prerequisites and rRun and nOut costs of the N best loops.  That
** information is gathered in the pBuilder->pOrSet object.  This special
** processing mode is used only for OR clause processing.
**
** When accumulating multiple loops (when pBuilder->pOrSet is NULL) we
** still might overwrite similar loops with the new template if the
** new template is better.  Loops may be overwritten if the following 
** conditions are met:
**
**    (1)  They have the same iTab.
**    (2)  They have the same iSortIdx.
**    (3)  The template has same or fewer dependencies than the current loop
**    (4)  The template has the same or lower cost than the current loop


*/
static int whereLoopInsert(WhereLoopBuilder *pBuilder, WhereLoop *pTemplate){
  WhereLoop **ppPrev, *p;
  WhereInfo *pWInfo = pBuilder->pWInfo;
  sqlite3 *db = pWInfo->pParse->db;

  /* If pBuilder->pOrSet is defined, then only keep track of the costs
  ** and prereqs.
  */
  if( pBuilder->pOrSet!=0 ){

      sqlite3DebugPrintf(x?"   or-%d:  ":"   or-X:  ", n);
      whereLoopPrint(pTemplate, pBuilder->pWC);
    }
#endif
    return SQLITE_OK;
  }

  /* Look for an existing WhereLoop to replace with pTemplate

  */
  whereLoopAdjustCost(pWInfo->pLoops, pTemplate);
  ppPrev = whereLoopFindLesser(&pWInfo->pLoops, pTemplate);







  if( ppPrev==0 ){
    /* There already exists a WhereLoop on the list that is better

    ** than pTemplate, so just ignore pTemplate */
#if WHERETRACE_ENABLED /* 0x8 */

    if( sqlite3WhereTrace & 0x8 ){

      sqlite3DebugPrintf("ins-noop: ");
      whereLoopPrint(pTemplate, pBuilder->pWC);
    }
















#endif

    return SQLITE_OK;  
  }else{















    p = *ppPrev;

  }

  /* If we reach this point it means that either p[] should be overwritten
  ** with pTemplate[] if p[] exists, or if p==NULL then allocate a new
  ** WhereLoop and insert it.
  */
#if WHERETRACE_ENABLED /* 0x8 */
  if( sqlite3WhereTrace & 0x8 ){
    if( p!=0 ){
      sqlite3DebugPrintf("ins-del:  ");
      whereLoopPrint(p, pBuilder->pWC);
    }
    sqlite3DebugPrintf("ins-new:  ");
    whereLoopPrint(pTemplate, pBuilder->pWC);
  }
#endif
  if( p==0 ){
    /* Allocate a new WhereLoop to add to the end of the list */
    *ppPrev = p = sqlite3DbMallocRaw(db, sizeof(WhereLoop));
    if( p==0 ) return SQLITE_NOMEM;
    whereLoopInit(p);
    p->pNextLoop = 0;
  }else{
    /* We will be overwriting WhereLoop p[].  But before we do, first
    ** go through the rest of the list and delete any other entries besides
    ** p[] that are also supplated by pTemplate */
    WhereLoop **ppTail = &p->pNextLoop;
    WhereLoop *pToDel;
    while( *ppTail ){
      ppTail = whereLoopFindLesser(ppTail, pTemplate);
      if( NEVER(ppTail==0) ) break;
      pToDel = *ppTail;
      if( pToDel==0 ) break;
      *ppTail = pToDel->pNextLoop;
#if WHERETRACE_ENABLED /* 0x8 */
      if( sqlite3WhereTrace & 0x8 ){
        sqlite3DebugPrintf("ins-del: ");
        whereLoopPrint(pToDel, pBuilder->pWC);
      }
#endif
      whereLoopDelete(db, pToDel);
    }
  }
  whereLoopXfer(db, p, pTemplate);


  if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
    Index *pIndex = p->u.btree.pIndex;
    if( pIndex && pIndex->tnum==0 ){
      p->u.btree.pIndex = 0;
    }
  }
  return SQLITE_OK;










}

/*
** Adjust the WhereLoop.nOut value downward to account for terms of the
** WHERE clause that reference the loop but which are not used by an
** index.
**

**   N>0:   N terms of the ORDER BY clause are satisfied
**   N==0:  No terms of the ORDER BY clause are satisfied
**   N<0:   Unknown yet how many terms of ORDER BY might be satisfied.   
**
** Note that processing for WHERE_GROUPBY and WHERE_DISTINCTBY is not as
** strict.  With GROUP BY and DISTINCT the only requirement is that
** equivalent rows appear immediately adjacent to one another.  GROUP BY
** and DISTINCT do not require rows to appear in any particular order as long
** as equivelent rows are grouped together.  Thus for GROUP BY and DISTINCT
** the pOrderBy terms can be matched in any order.  With ORDER BY, the 
** pOrderBy terms must be matched in strict left-to-right order.
*/
static i8 wherePathSatisfiesOrderBy(
  WhereInfo *pWInfo,    /* The WHERE clause */
  ExprList *pOrderBy,   /* ORDER BY or GROUP BY or DISTINCT clause to check */

         && j>=pLoop->u.btree.nEq
         && pIndex->pTable->aCol[iColumn].notNull==0
        ){
          isOrderDistinct = 0;
        }

        /* Find the ORDER BY term that corresponds to the j-th column
        ** of the index and mark that ORDER BY term off 
        */
        bOnce = 1;
        isMatch = 0;
        for(i=0; bOnce && i<nOrderBy; i++){
          if( MASKBIT(i) & obSat ) continue;
          pOBExpr = sqlite3ExprSkipCollate(pOrderBy->a[i].pExpr);
          testcase( wctrlFlags & WHERE_GROUPBY );

      if( (obSat&m)==m ) return i;
    }
    return 0;
  }
  return -1;
}


/*
** If the WHERE_GROUPBY flag is set in the mask passed to sqlite3WhereBegin(),
** the planner assumes that the specified pOrderBy list is actually a GROUP
** BY clause - and so any order that groups rows as required satisfies the
** request.
**
** Normally, in this case it is not possible for the caller to determine
** whether or not the rows are really being delivered in sorted order, or
** just in some other order that provides the required grouping. However,
** if the WHERE_SORTBYGROUP flag is also passed to sqlite3WhereBegin(), then
** this function may be called on the returned WhereInfo object. It returns
** true if the rows really will be sorted in the specified order, or false
** otherwise.
**
** For example, assuming:
**
**   CREATE INDEX i1 ON t1(x, Y);
**
** then
**
**   SELECT * FROM t1 GROUP BY x,y ORDER BY x,y;   -- IsSorted()==1
**   SELECT * FROM t1 GROUP BY y,x ORDER BY y,x;   -- IsSorted()==0
*/
int sqlite3WhereIsSorted(WhereInfo *pWInfo){
  assert( pWInfo->wctrlFlags & WHERE_GROUPBY );
  assert( pWInfo->wctrlFlags & WHERE_SORTBYGROUP );
  return pWInfo->sorted;
}

#ifdef WHERETRACE_ENABLED
/* For debugging use only: */
static const char *wherePathName(WherePath *pPath, int nLoop, WhereLoop *pLast){
  static char zName[65];
  int i;
  for(i=0; i<nLoop; i++){ zName[i] = pPath->aLoop[i]->cId; }
  if( pLast ) zName[i++] = pLast->cId;
  zName[i] = 0;
  return zName;
}
#endif


/*
** Given the list of WhereLoop objects at pWInfo->pLoops, this routine
** attempts to find the lowest cost path that visits each WhereLoop
** once.  This path is then loaded into the pWInfo->a[].pWLoop fields.
**
** Assume that the total number of output rows that will need to be sorted

        pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
      }
    }else{
      pWInfo->nOBSat = pFrom->isOrdered;
      if( pWInfo->nOBSat<0 ) pWInfo->nOBSat = 0;
      pWInfo->revMask = pFrom->revLoop;
    }
    if( (pWInfo->wctrlFlags & WHERE_SORTBYGROUP)
        && pWInfo->nOBSat==pWInfo->pOrderBy->nExpr
    ){
      Bitmask notUsed = 0;
      int nOrder = wherePathSatisfiesOrderBy(pWInfo, pWInfo->pOrderBy, 
          pFrom, 0, nLoop-1, pFrom->aLoop[nLoop-1], &notUsed
      );
      assert( pWInfo->sorted==0 );
      pWInfo->sorted = (nOrder==pWInfo->pOrderBy->nExpr);
    }
  }


  pWInfo->nRowOut = pFrom->nRow;

  /* Free temporary memory and return success */
  sqlite3DbFree(db, pSpace);
  return SQLITE_OK;
}

    if( pTabItem->viaCoroutine && !db->mallocFailed ){
      last = sqlite3VdbeCurrentAddr(v);
      k = pLevel->addrBody;
      pOp = sqlite3VdbeGetOp(v, k);
      for(; k<last; k++, pOp++){
        if( pOp->p1!=pLevel->iTabCur ) continue;
        if( pOp->opcode==OP_Column ){
          pOp->opcode = OP_Copy;
          pOp->p1 = pOp->p2 + pTabItem->regResult;
          pOp->p2 = pOp->p3;
          pOp->p3 = 0;
        }else if( pOp->opcode==OP_Rowid ){
          pOp->opcode = OP_Null;
          pOp->p1 = 0;
          pOp->p3 = 0;

  ExprList *pOrderBy;       /* The ORDER BY clause or NULL */
  ExprList *pResultSet;     /* Result set. DISTINCT operates on these */
  WhereLoop *pLoops;        /* List of all WhereLoop objects */
  Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
  LogEst nRowOut;           /* Estimated number of output rows */
  u16 wctrlFlags;           /* Flags originally passed to sqlite3WhereBegin() */
  i8 nOBSat;                /* Number of ORDER BY terms satisfied by indices */
  u8 sorted;                /* True if really sorted (not just grouped) */
  u8 okOnePass;             /* Ok to use one-pass algorithm for UPDATE/DELETE */
  u8 untestedTerms;         /* Not all WHERE terms resolved by outer loop */
  u8 eDistinct;             /* One of the WHERE_DISTINCT_* values below */
  u8 nLevel;                /* Number of nested loop */
  int iTop;                 /* The very beginning of the WHERE loop */
  int iContinue;            /* Jump here to continue with next record */
  int iBreak;               /* Jump here to break out of the loop */

  INSERT INTO t16a VALUES('cba',5.5,98,'fizzle');
  SELECT * FROM t16a ORDER BY a;
} {abc 1.25 99 xyzzy cba 5.5 98 fizzle}
do_execsql_test alter-16.2 {
  ALTER TABLE t16a RENAME TO t16a_rn;
  SELECT * FROM t16a_rn ORDER BY a;
} {abc 1.25 99 xyzzy cba 5.5 98 fizzle}

#-------------------------------------------------------------------------
# Verify that NULL values into the internal-use-only sqlite_rename_*()
# functions do not cause problems.
#
do_execsql_test alter-17.1 {
  SELECT sqlite_rename_table('CREATE TABLE xyz(a,b,c)','abc');
} {{CREATE TABLE "abc"(a,b,c)}}
do_execsql_test alter-17.2 {
  SELECT sqlite_rename_table('CREATE TABLE xyz(a,b,c)',NULL);
} {{CREATE TABLE "(NULL)"(a,b,c)}}
do_execsql_test alter-17.3 {
  SELECT sqlite_rename_table(NULL,'abc');
} {{}}
do_execsql_test alter-17.4 {
  SELECT sqlite_rename_trigger('CREATE TRIGGER r1 ON xyz WHEN','abc');
} {{CREATE TRIGGER r1 ON "abc" WHEN}}
do_execsql_test alter-17.5 {
  SELECT sqlite_rename_trigger('CREATE TRIGGER r1 ON xyz WHEN',NULL);
} {{CREATE TRIGGER r1 ON "(NULL)" WHEN}}
do_execsql_test alter-17.6 {
  SELECT sqlite_rename_trigger(NULL,'abc');
} {{}}
do_execsql_test alter-17.7 {
  SELECT sqlite_rename_parent('CREATE TABLE t1(a REFERENCES "xyzzy")',
         'xyzzy','lmnop');
} {{CREATE TABLE t1(a REFERENCES "lmnop")}}
do_execsql_test alter-17.8 {
  SELECT sqlite_rename_parent('CREATE TABLE t1(a REFERENCES "xyzzy")',
         'xyzzy',NULL);
} {{CREATE TABLE t1(a REFERENCES "(NULL)")}}
do_execsql_test alter-17.9 {
  SELECT sqlite_rename_parent('CREATE TABLE t1(a REFERENCES "xyzzy")',
         NULL, 'lmnop');
} {{}}
do_execsql_test alter-17.10 {
  SELECT sqlite_rename_parent(NULL,'abc','xyz');
} {{}}

finish_test

do_test func-29.3 {
  db close
  sqlite3 db test.db
  sqlite3_db_status db CACHE_MISS 1
  db eval {SELECT typeof(+x) FROM t29 ORDER BY id}
} {integer null real blob text}
if {[permutation] != "mmap"} {
  ifcapable !direct_read {
    do_test func-29.4 {
      set x [lindex [sqlite3_db_status db CACHE_MISS 1] 1]
      if {$x>100} {set x many}
      set x
    } {many}
  }
}
do_test func-29.5 {
  db close
  sqlite3 db test.db
  sqlite3_db_status db CACHE_MISS 1
  db eval {SELECT sum(length(x)) FROM t29}
} {1000009}

do_execsql_test index6-5.0 {
  CREATE INDEX t3b ON t3(b) WHERE xyzzy.t3.b BETWEEN 5 AND 10;
                               /* ^^^^^-- ignored */
  ANALYZE;
  SELECT count(*) FROM t3 WHERE t3.b BETWEEN 5 AND 10;
  SELECT stat+0 FROM sqlite_stat1 WHERE idx='t3b';
} {6 6}

# Test case for ticket [2ea3e9fe6379fc3f6ce7e090ce483c1a3a80d6c9] from
# 2014-04-13: Partial index causes assertion fault on UPDATE OR REPLACE.
#
do_execsql_test index6-6.0 {
  CREATE TABLE t6(a,b);
  CREATE UNIQUE INDEX t6ab ON t1(a,b);
  CREATE INDEX t6b ON t6(b) WHERE b=1;
  INSERT INTO t6(a,b) VALUES(123,456);
  SELECT * FROM t6;
} {123 456}
do_execsql_test index6-6.1 {
  UPDATE OR REPLACE t6 SET b=789;
  SELECT * FROM t6;
} {123 789}
do_execsql_test index6-6.2 {
  PRAGMA integrity_check;
} {ok}


finish_test

# 2014-04-21
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
#
# Test that ticket [b75a9ca6b0] has been fixed.
#
# Ticket [b75a9ca6b0] concerns queries that have both a GROUP BY
# and an ORDER BY.  This code verifies that SQLite is able to
# optimize out the ORDER BY in some circumstances, but retains the
# ORDER BY when necessary.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix tkt-b75a9ca6b0

do_execsql_test 1 {
  CREATE TABLE t1 (x, y);
  INSERT INTO t1 VALUES (1, 3); 
  INSERT INTO t1 VALUES (2, 2);
  INSERT INTO t1 VALUES (3, 1);
}

do_execsql_test 1.1 {
  CREATE INDEX i1 ON t1(x, y);
} 

set idxscan {0 0 0 {SCAN TABLE t1 USING COVERING INDEX i1}}
set tblscan {0 0 0 {SCAN TABLE t1}}
set grpsort {0 0 0 {USE TEMP B-TREE FOR GROUP BY}}
set sort    {0 0 0 {USE TEMP B-TREE FOR ORDER BY}}

foreach {tn q res eqp} [subst -nocommands {
  1 "SELECT * FROM t1 GROUP BY x, y ORDER BY x,y"
  {1 3  2 2  3 1} {$idxscan}

  2 "SELECT * FROM t1 GROUP BY x, y ORDER BY x"
  {1 3  2 2  3 1} {$idxscan $sort}

  3 "SELECT * FROM t1 GROUP BY y, x ORDER BY y, x"
  {3 1  2 2  1 3} {$idxscan $sort}
  
  4 "SELECT * FROM t1 GROUP BY x ORDER BY x"
  {1 3  2 2  3 1} {$idxscan}

  5 "SELECT * FROM t1 GROUP BY y ORDER BY y"
  {3 1  2 2  1 3} {$tblscan $grpsort}

  6 "SELECT * FROM t1 GROUP BY y ORDER BY x"
  {1 3  2 2  3 1} {$tblscan $grpsort $sort}

  7 "SELECT * FROM t1 GROUP BY x, y ORDER BY x, y DESC"
  {1 3  2 2  3 1} {$idxscan $sort}

  8 "SELECT * FROM t1 GROUP BY x, y ORDER BY x DESC, y DESC"
  {3 1  2 2  1 3} {$idxscan $sort}

  9 "SELECT * FROM t1 GROUP BY x, y ORDER BY x ASC, y ASC"
  {1 3  2 2  3 1} {$idxscan}

  10 "SELECT * FROM t1 GROUP BY x, y ORDER BY x COLLATE nocase, y"
  {1 3  2 2  3 1} {$idxscan $sort}

}] {
  do_execsql_test 1.$tn.1 $q $res
  do_eqp_test     1.$tn.2 $q $eqp
}


finish_test

  } [wal_file_size 1 1024]
}

db close
sqlite3_shutdown
test_sqlite3_log
sqlite3_initialize

# Make sure PRAGMA journal_mode=WAL works with ATTACHED databases in
# all journal modes.
#
foreach mode {OFF MEMORY PERSIST DELETE TRUNCATE WAL} {
  delete_file test.db test2.db
  sqlite3 db test.db
  do_test wal-25.$mode {
    db eval "PRAGMA journal_mode=$mode"
    db eval {ATTACH 'test2.db' AS t2; PRAGMA journal_mode=WAL;}
  } {wal}
  db close
}

finish_test

} {3 4 3 4}
do_execsql_test 4.7 {
  SELECT * FROM t44 LEFT JOIN t46 ON a=c
   WHERE d=4 OR d IS NULL
   ORDER BY a;
} {3 4 3 4}

# Verify fix of a bug reported on the mailing list by Peter Reid
#
do_execsql_test 5.1 {
  DROP TABLE IF EXISTS t;
  CREATE TABLE t(c0,c1,c2,c3,c4,c5,c6,c7,c8,c9,c10,c11,c12,c13,c14,c15,c16,c17);
  CREATE INDEX tc0 ON t(c0);
  CREATE INDEX tc1 ON t(c1);
  CREATE INDEX tc2 ON t(c2);
  CREATE INDEX tc3 ON t(c3);
  CREATE INDEX tc4 ON t(c4);
  CREATE INDEX tc5 ON t(c5);
  CREATE INDEX tc6 ON t(c6);
  CREATE INDEX tc7 ON t(c7);
  CREATE INDEX tc8 ON t(c8);
  CREATE INDEX tc9 ON t(c9);
  CREATE INDEX tc10 ON t(c10);
  CREATE INDEX tc11 ON t(c11);
  CREATE INDEX tc12 ON t(c12);
  CREATE INDEX tc13 ON t(c13);
  CREATE INDEX tc14 ON t(c14);
  CREATE INDEX tc15 ON t(c15);
  CREATE INDEX tc16 ON t(c16);
  CREATE INDEX tc17 ON t(c17);
  
  INSERT INTO t(c0, c16) VALUES (1,1);
  
  SELECT * FROM t WHERE
    c0=1 or  c1=1 or  c2=1 or  c3=1 or
    c4=1 or  c5=1 or  c6=1 or  c7=1 or
    c8=1 or  c9=1 or c10=1 or c11=1 or
    c12=1 or c13=1 or c14=1 or c15=1 or
    c16=1 or c17=1;
} {1 {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} 1 {}}
do_execsql_test 5.2 {
  DELETE FROM t;
  INSERT INTO t(c0,c17) VALUES(1,1);
  SELECT * FROM t WHERE
    c0=1 or  c1=1 or  c2=1 or  c3=1 or
    c4=1 or  c5=1 or  c6=1 or  c7=1 or
    c8=1 or  c9=1 or c10=1 or c11=1 or
    c12=1 or c13=1 or c14=1 or c15=1 or
    c16=1 or c17=1;
} {1 {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} {} 1}
do_execsql_test 5.3 {
  DELETE FROM t;
  INSERT INTO t(c0,c15) VALUES(1,1);
  SELECT * FROM t WHERE
    c0=1 or  c1=1 or  c2=1 or  c3=1 or
    c4=1 or  c5=1 or  c6=1 or  c7=1 or
    c8=1 or  c9=1 or c10=1 or c11=1 or
    c12=1 or c13=1 or c14=1 or c15=1 or
    c16=1 or c17=1;
} {1 {} {} {} {} {} {} {} {} {} {} {} {} {} {} 1 {} {}}


finish_test

} {/.*SCAN TABLE a.*SEARCH TABLE b USING INDEX .*b_1 .b1=..*/}
do_eqp_test whereG-3.3 {
  SELECT * FROM a, b WHERE a2=5 AND b1=a1;
} {/.*SCAN TABLE a.*SEARCH TABLE b USING INDEX .*b_1 .b1=..*/}
do_eqp_test whereG-3.4 {
  SELECT * FROM a, b WHERE a2=5 AND a1=b1;
} {/.*SCAN TABLE a.*SEARCH TABLE b USING INDEX .*b_1 .b1=..*/}

# Ticket [1e64dd782a126f48d78c43a664844a41d0e6334e]:
# Incorrect result in a nested GROUP BY/DISTINCT due to the use of an OP_SCopy
# where an OP_Copy was needed.
#
do_execsql_test whereG-4.0 {
  CREATE TABLE t4(x);
  INSERT INTO t4 VALUES('right'),('wrong');
  SELECT DISTINCT x
   FROM (SELECT x FROM t4 GROUP BY x)
   WHERE x='right'
   ORDER BY x;
} {right}


finish_test

# 2014-03-31
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# 
# Test cases for query planning decisions where one candidate index
# covers a proper superset of the WHERE clause terms of another
# candidate index.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

do_execsql_test whereH-1.1 {
  CREATE TABLE t1(a,b,c,d);
  CREATE INDEX t1abc ON t1(a,b,c);
  CREATE INDEX t1bc ON t1(b,c);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
} {/INDEX t1abc /}
do_execsql_test whereH-1.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
} {~/TEMP B-TREE FOR ORDER BY/}

do_execsql_test whereH-2.1 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c,d);
  CREATE INDEX t1bc ON t1(b,c);
  CREATE INDEX t1abc ON t1(a,b,c);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
} {/INDEX t1abc /}
do_execsql_test whereH-2.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c>=? ORDER BY c;
} {~/TEMP B-TREE FOR ORDER BY/}

do_execsql_test whereH-3.1 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c,d,e);
  CREATE INDEX t1cd ON t1(c,d);
  CREATE INDEX t1bcd ON t1(b,c,d);
  CREATE INDEX t1abcd ON t1(a,b,c,d);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {/INDEX t1abcd /}
do_execsql_test whereH-3.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {~/TEMP B-TREE FOR ORDER BY/}

do_execsql_test whereH-4.1 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c,d,e);
  CREATE INDEX t1cd ON t1(c,d);
  CREATE INDEX t1abcd ON t1(a,b,c,d);
  CREATE INDEX t1bcd ON t1(b,c,d);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {/INDEX t1abcd /}
do_execsql_test whereH-4.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {~/TEMP B-TREE FOR ORDER BY/}

do_execsql_test whereH-5.1 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c,d,e);
  CREATE INDEX t1bcd ON t1(b,c,d);
  CREATE INDEX t1cd ON t1(c,d);
  CREATE INDEX t1abcd ON t1(a,b,c,d);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {/INDEX t1abcd /}
do_execsql_test whereH-5.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {~/TEMP B-TREE FOR ORDER BY/}

do_execsql_test whereH-6.1 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c,d,e);
  CREATE INDEX t1bcd ON t1(b,c,d);
  CREATE INDEX t1abcd ON t1(a,b,c,d);
  CREATE INDEX t1cd ON t1(c,d);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {/INDEX t1abcd /}
do_execsql_test whereH-6.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {~/TEMP B-TREE FOR ORDER BY/}

do_execsql_test whereH-7.1 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c,d,e);
  CREATE INDEX t1abcd ON t1(a,b,c,d);
  CREATE INDEX t1bcd ON t1(b,c,d);
  CREATE INDEX t1cd ON t1(c,d);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {/INDEX t1abcd /}
do_execsql_test whereH-7.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {~/TEMP B-TREE FOR ORDER BY/}

do_execsql_test whereH-8.1 {
  DROP TABLE t1;
  CREATE TABLE t1(a,b,c,d,e);
  CREATE INDEX t1abcd ON t1(a,b,c,d);
  CREATE INDEX t1cd ON t1(c,d);
  CREATE INDEX t1bcd ON t1(b,c,d);

  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {/INDEX t1abcd /}
do_execsql_test whereH-8.2 {
  EXPLAIN QUERY PLAN
  SELECT d FROM t1 WHERE a=? AND b=? AND c=? AND d>=? ORDER BY d;
} {~/TEMP B-TREE FOR ORDER BY/}



finish_test